Rosseter is producing raw deposits of two main nanotube products,
- short Multi Wall Nano Tubes (sh‑MWNTs) and
- t헎Ts, sp‑MWNTs
TEM pictures the nanotube deposits appear as mixtures of the sh‑MWNTs
and carbon polyhedral nanoparticles, with admixtures of different
graphitic carbons and short Single Wall Nano Tubes (sh‑SWNTs).
rest of Rosseter's products (Ros3-Ros5) are by‑products of the two
main processes. The by‑products contain few nanotubes and are mostly
composed of different forms of disordered graphite (DOG) and Graphite
Nano Fibers (GNFs).
produced in our main process with no use of catalysts.
part of sh‑MWNTs in Ros1 seem to be nested (Russian doll‑like
structure) MWNTs having semi‑spherical and conical-like (or faceted)
caps [see HR-TEM in Fig.3,a,b].
contains (see typical TEM images in Fig.4 and Fig.5)
50-80wt% of MWNTs and 15-35% of carbon polyhedral nanoparticles, and
the rest are different forms of disordered graphite including single
graphite sheets, graphite platelets, 駨t sootnoscales, traces
of SWNTs (Fig.3c), etc.
Inorganic impurities are not higher than 0.5wt% and can be easily
removed by successful washing in inorganic acids (HCl, HNO3,
Typical X-Ray Diffraction patterns and Micro-Raman spectra are shown
in Fig.6. XRD reveals two main interlayer distances in the sh‑MWNTs,
0.341 and 0.345 nm (Fig.6). HR-TEM reveals essentially increased
interlayer distances (up to 0.375 nm), especially, for thinner sh‑MWNTs
MWNTs튠 length and diameter distributions are characterized by three-modal
distributions with maximums at ~200, 300 and 500 nm for lengths, ~6.5,
12 and 20 nm for outer diameters and 2.6, 4.0 and 6.7 nm for inner
diameters (the distributions are presented in Fig.7,d)
Ros1 - Field Electron Emission
MWNTs䩡meter distribution provides excellent Field Electron
Emission (FEE) properties. Rough powders of Ros1 start Field
Electron Emission (EE) at a threshold of 2‑2.5V/micron, demonstrating
intensity currents of 0.5-1 mA/cm2 at electric fields of
Typical FEE I-V-curves are shown in Fig.8 (under the test a
powdered Ros1 sample is pressed into a hollow with a cross section of
FEE parameters strongly depend on admixtures of the graphitic forms
(see Fig.9). Separation of the graphitic forms allows improving
Ros1 - Composites
MWNTs쥮gth distribution provides a very good dispersivity (see TEM
in Fig.5), solubilization and functionalization of the MWNTs
that facilitates producing Composites possessing
improved mechanical characteristics even at very low loads of raw
of just ~1% of raw Ros1 in PVA improve Young modulus, strength
tensile, toughness and electric conductivity in 1.5, 1.75, 2 and 104
times, respectively, in comparison with the blank PVA film (Fig.10,a,b)(Fig.10,c).
composites prepared by electro-codeposition of metals and our sh‑MWNTs
(Ros1) exhibit a remarkable improvement of hardness and a decrease of
the wear volume in comparison with the blank metal matrix.
Ros1 - BET Surface Area
surface area is 6.5-10 m2/g (rough powders). Pore area is
about 90-95% of the BET (see graphs in Fig.11).
Hydrogen storage in 10g-powder-samples at room temperature and
pressure of ~100 atm is low, ~ 0.1-0.2wt%. Better storage is expected
for oxidized nanotubes.
tubes are well graphitised and can sustain long oxidation in air and
acids (H2SO4, HNO3, HCl, HF/HNO3,
etc). In air perceptible losses of weight (≥2-3rel.%) are achieved for
time less than 10-15 min at temperatures higher than 600oC.
Typical TGA are shown in Fig.12.
MWNTs usually have one semispherical and one conical cap. Under a
proper oxidation (for instant, in air at ~600oC for ~ 45-60
min) the semispherical caps are opened in first turn leaving the
conical ones almost intact (HR-TEM in Fig.13).
Further characteristics of Ros1 are coming soon
This is a product mainly containing the MWNTs and polyhedral
A new technique of quantitative separation of the MWNTs from the
graphitic carbons is under development.
The technique allows separating large quantities of raw Ros1 powders
into 2 fractions, the MWNTs & nanoparticles (see TEM in Fig.14)
and the graphitic carbons (see TEM in Fig.15). As a result, FEE
from Ros1‑p is highly improved (Fig.9).
Ros2, as produced
is produced in a modified process with use of Co/Ni catalysts.
(as produced) contains ~50 wt% of short MWNTs, ~ 20% of carbon
polyhedral nanoparticles and the rest are different graphitic forms
(highly-disordered graphite, single graphite sheets, graphite
platelets, 駨t soot৲aphitic scales, traces of SWNTs, etc (see
typical TEM images in Fig.16, Fig.17,Fig.18).
HR‑TEM pictures (Fig.19, Fig.20) the most part of Ros‑2
MWNTs exhibit asymmetrical wall-thickness and the extra thickness is
concentrated in some isolated singular fringe spacings, which are
concentrated in one wall of the MWNTs. This effect can be explained by
assuming that the sp‑MWNTs partially consist of scrolls instead of
nested cylindrical tubules. The scrolls introduce extra‑space between
the layers, the space is usually double of the normal value, i.e. it
is ~0.7 nm, but sometimes the spaces of ~1.05 nm and even ~1.4 nm are
seen in HR‑TEM pictures of the sp‑MWNTs.
comparison with Ros1 sh‑MWNTs Ros2 MWNTs are essentially elongated and
thickened (see length and diameter distributions in
opening the entries by a careful oxidation, the extra‑space provides
additional channels for
Gas & Energy storage
Further characteristics of Ros2 are coming soon
by-product of the modified process (Ros2) appears as mainly composed
of DOG in shapes of spherical curly lumps, platelets and single sheets
(Fig.21). Also different forms of GNFs, partially graphitized
soot particles, 駨t㯯t and Co/Ni nanoparticles are seen in
typical TEM images of Ros3 [Fig.22].
especially oxidized and annealed, Ros-3 samples of 10 grams
demonstrated high Hydrogen uptakes at room temperature and moderate
Further characteristics of Ros3 are coming soon
Gaseous hydrocarbons released in both processes (Ros1/Ros2) are
partially converted in Ros4 which is composed of different forms of
DOG with traces of MWNTs (Figs.24,a,b,c).
is produced as monolithic dense (~1.7g/cm3) thin (50-200 μm)
coatings over refractory metals and can be produced as pipes with
inner diameters of 1-3 mm and wall thicknes of 50-500 μm.
Powdered Ros4 demonstrates a rather stable but low FEE.
Further characteristics of Ros4 are coming soon
by‑product of our main process (Ros1) is very similar to Ros3 but it
contains no metal nanoparticles and few GNFs (see Fig.25).
Short SWNTs are traces in Ros5 as well.
shows typical HR-TEM images of DOG sheets and curly lumps.
Further characteristics of Ros5 are coming soon
Gaseous hydrocarbons released in the modified process are partially
converted in Ros6. In TEM pictures Ros6 appears as a mixture of long
GNFs, bimodal soot particles and Co/Ni nanoparticles (Fig.27).
HR‑TEM shows herringbone structure of the GNFs (Fig.28) and
partially‑graphitized structure of the soot particles (Fig.29).
Further characteristics of Ros6 are coming soon.